EP0458760A1 - Procédé et installation pour l'épuration biologique d'eau usée - Google Patents

Procédé et installation pour l'épuration biologique d'eau usée Download PDF

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Publication number
EP0458760A1
EP0458760A1 EP19910830193 EP91830193A EP0458760A1 EP 0458760 A1 EP0458760 A1 EP 0458760A1 EP 19910830193 EP19910830193 EP 19910830193 EP 91830193 A EP91830193 A EP 91830193A EP 0458760 A1 EP0458760 A1 EP 0458760A1
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EP
European Patent Office
Prior art keywords
treatment
environment
compartment
aerobic
sector
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP19910830193
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German (de)
English (en)
Inventor
Alexander William Versfeld
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FOSFLEX Srl
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FOSFLEX Srl
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Publication date
Application filed by FOSFLEX Srl filed Critical FOSFLEX Srl
Publication of EP0458760A1 publication Critical patent/EP0458760A1/fr
Withdrawn legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/02—Aerobic processes
    • C02F3/12—Activated sludge processes
    • C02F3/1236—Particular type of activated sludge installations
    • C02F3/1242—Small compact installations for use in homes, apartment blocks, hotels or the like
    • C02F3/1247—Small compact installations for use in homes, apartment blocks, hotels or the like comprising circular tanks with elements, e.g. decanters, aeration basins, in the form of segments, crowns or sectors
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/30—Aerobic and anaerobic processes
    • C02F3/301—Aerobic and anaerobic treatment in the same reactor
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/30—Aerobic and anaerobic processes
    • C02F3/308—Biological phosphorus removal
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/20—Controlling water pollution; Waste water treatment
    • Y02A20/208—Off-grid powered water treatment
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Definitions

  • the present invention relates to a biological process, and to plant, for the purification of sewage, that is to say, soiled liquids discharged from dwellings and/or industrial effluents which contain pollutants carried in the form of organic, nitrogenous, phosphorated and other substances.
  • sewage that is to say, soiled liquids discharged from dwellings and/or industrial effluents which contain pollutants carried in the form of organic, nitrogenous, phosphorated and other substances.
  • the process and plant disclosed are embraced by the art field of activated sludge treatment.
  • Activated sludge systems are designed specifically to remove phosphorus, nitrogen and other common organic pollutants from sewage by a biological process. It is acknowledged that the extraction of phosphorus can be stepped up by exploiting the natural tendency of certain bacteria to gather in large quantities of polyphosphates by intracellular accumulation. Accordingly, to set up an activated sludge plant with optimum phosphorus extraction capacities, conditions must be created within the system which favour the profileration and growth of these bacteria in preference to those not naturally possessing the ability to absorb large quantities of polyphosphates intracellularly.
  • polyphosphatic organisms need to grow, preferably, on a substrate of lower, i.e. short chain fatty acids in anaerobic conditions, that is to say, in an environment free from oxygen and nitrates. Given anaerobic conditions and the presence of lower fatty acids, such polyphosphatic organisms can break down or hydrolize polyphosphate chains, releasing phosphate into the surrounding liquid; thus one obtains the release of phosphate occurring in an anaerobic environment.
  • the bond energy liberated in this way is used to absorb, complexify and store up lower fatty acids within the organism, which thus sequesters the substrate for its own exclusive use on entering an environment containing collectors of external electrons.
  • the polyphosphatic organisms utilize the sequestered substrate both to promote growth, and as a means by which to replenish their reserves of polyphosphates by extracting phosphate from the surrounding medium; this occasions the intake of excess phosphate, occurring in anoxic and aerobic environments.
  • sewage may contain substantial amounts of industrial waste and the concentration of short chain fatty acids is already high, such fermentation is not required; rather, fermentation becomes necessary when the concentration of short chain fatty acids is relatively low, for example as in sewage containing prevalently domestic waste. Accordingly, to favour the growth of polyphosphatic organisms, it is necessary to create an anaerobic environment with a high concentration of fatty acids, and an aerobic environment that will enable the intake of phosphate.
  • primary sedimentation tanks are used to favour the production of lower fatty acids by fermentation; more exactly, the underflow or sediment produced in the primary sedimentation tank is discharged into a gravity thickener, and a part of the thickened solids then recycled back into the sedimentation tank, in such a way as to create a bed of sludge.
  • the treatment system must incorporate some suitable means of matching the proportion of unaerated sludge to given operating conditions.
  • the object of the present invention is to overcome the limitations and the drawbacks of conventional processes and plant.
  • the object in question consists in setting forth a new process and new plant for the purification of sewage by biological means, capable of providing such operational flexibility as is required in order to effect a treatment adaptable to varying conditions of raw sewage that occur over periods of time, and without any need for modification of or structural alterations to the installation.
  • a conventional process for the biological treatment of sewage consists in a continuous cycle including primary sedimentation SP, brought about by fermentation; the products of such fermentation are elutriated in the flow of sewage W directed into a reactor to undergo a first step of treatment in an unaerated environment 2, followed by further treatment in an aerobic environment 3.
  • the unaerated environment 2 is divided up into a plurality of diversified treatment sectors 6; also, the system comprises at least one recycle S through which activated sludge from the underflow produced in secondary clarification is returned to the reactor, and a further recycle A through which liquid L is directed from the aerobic environment 3 back into one of the treatment sectors 6 of the unaerated environment 2.
  • the process disclosed also envisages a recycle R of liquid L from one of the treatment sectors 6 of the unaerated environment 2 back into another unaerated sector 6.
  • the unaerated environment 2 is such as to enable a diversity of treatments, and contains no oxygen introduced by means of aeration; according to the invention, the environment 2 in question is partitioned off into an anaerobic sub-environment i.e. free of oxygen and nitrates, and an anoxic sub-environment, i.e. free of oxygen but containing nitrates, each consisting in a plurality of single treatment sectors 6 of which the distribution in terms of position and number will depend upon the selected type of operation, as is explained in due course.
  • plant according to the invention suitable for the implementation of a biological sewage treatment process as described above comprises a primary sedimentation tank SP, and a reactor, denoted 1 in its entirety, into which the products of fermentation are directed together with the flow of sewage W.
  • the primary sedimentation tank SP is optional, given that the process can also operate without primary sedimentation if the concentration of short chain fatty acids in the raw sewage is of an acceptable order; thus, W can denote either settled or raw sewage, according to whether primary sedimentation tanks SP are in use or not in use, respectively.
  • the reactor 1 is embodied preferably as a first unaerated treatment tank 2, and a second aerobic treatment tank 3 that is connected with secondary sedimentation and clarification tanks SS.
  • the reactor 1 comprises a first centrally located and preferably circular chamber 4 in which the raw or settled sewage W is collected, surrounded by a second chamber 5 for collection of the activated sludge, an unaerated treatment tank 2 and an aerobic treatment tank 3, all preferably of annular geometry and disposed concentrically and coaxially around the first chamber 4.
  • the unaerated tank 2 is divided into a plurality of compartments 6 communicating one with the next along the direction of flow, in which diversified types of treatment of the liquid L are effected, and the first and second chambers 4 and 5 can be connected, independently of each other, with all of the compartments 6 of the unaerated tank 2.
  • conduits 8 and 9 and control mechanisms 7 are effected by means of conduits 8 and 9 and control mechanisms 7; such mechanisms will consist essentially in valves or shutters, etc., capable of allowing or disallowing flow from one chamber or compartment to another, also of regulating volume and velocity of the flow.
  • At least one of the compartments 6 of the unaerated tank 2 can be connected directly with at least one other compartment 6 located other than immediately adjacent, by way of a pump denoted 17.
  • the compartments 6 are divided into two groups, one of which effecting anaerobic treatment, the other anoxic treatment.
  • compartments 6 making up the unaerated tank 2 Whilst the number of compartments 6 making up the unaerated tank 2 is variable and in no way limited, the example of the drawings, based on design and operational requirements, shows six such divisions denoted 10, 11...15, of which the numbering follows the flow of the liquid L and terminates at the compartment 15 connecting finally with the aerobic tank 3.
  • the compartments denoted 10 and 11 are allocated to anaerobic treatment, and those denoted 12, 13, 14 and 15 allocated to anoxic treatment.
  • activated sludge recycled to the second chamber 5 via the route denoted S can be directed into the first unaerated compartment 10, simultaneously with but separately from the flow of sewage W from the first chamber 4.
  • Treated liquid L is also recycled from the aerobic tank 3 to the first anoxic compartment 12 by pumping through A.
  • This first configuration optimizes the extraction of nitrogen, as anoxic volume is maximized through the effect of recycling nitrates by way of route A.
  • compartments 10 and 11 are anoxic
  • 12 and 13 are anaerobic
  • 14 and 15 anoxic
  • activated sludge recycled through S can be directed from the second chamber 5 into the first compartment 10 of the first of the two anoxic groups.
  • Sewage W passes direct from the first chamber 4 through a conduit 8 into the first 12 of the two anaerobic treatment compartments, whilst liquid L in the aerobic tank 3 is pumped via A back into the first compartment 14 of the second anoxic group.
  • the first group of two anoxic compartments 10 and 11 serves exclusively to denitrify the nitrates entering with the sludge recycle S, in consequence of which, sludge returned to,the first anaerobic compartment 12 contains markedly low concentrations of oxygen and nitrates, and there is a much reduced presence of electron collectors in the unaerated environment by virtue of the oxidating action of heterotrophic bacteria.
  • sewage W is discharged into the compartment denoted 10, with recycling sludge and liquid (S and A) redirected into the compartment denoted 13, and by introducing a third recycle R, liquid L is also pumped from the last compartment 15 back to the first 10.
  • sewage W is directed from the first chamber 4 into the first anaerobic treatment compartment 10.
  • Sludge recycled through S is directed from the second chamber 5 to the first anoxic treatment compartment 13, entering simultaneously with but separately from liquid L recycled through A from the aerobic tank 3, and to reiterate, there is the further recycle through R of liquid L from the last compartment 15 of the anoxic group to the first compartment 10 of the anaerobic.
  • the recycle through R contains a quantity of activated sludge notably free of nitrates and oxygen, and moreover, with a low concentration of activated sludge in the anaerobic treatment compartments, the proportion of unaerated mass overall is minimal, and the risk of the bulking in the sludge thus averted.
  • the fourth configuration illustrated (fig 5) is identical to the third, save for the fact that the liquid L recycled through A is discharged into the compartment denoted 14, and the inter-compartmental recycle R occurs by pumping through a conduit 9 from compartment 13 to compartment 10.
  • raw or settled sewage W is directed from the first chamber 4 into the first anaerobic compartment 10; sludge recycled through S back to the second chamber 5 is directed into the first compartment 13 of the anoxic group, and liquid L is recycled through A from the aerobic tank 3 to compartment 14 of the anoxic group.
  • the additional recycle through R from the compartment denoted 13 contains reduced quantities of nitrates, regardless of the rate of flow at A, thus positively influencing the extraction of phosphorus by biological means.
  • the aerobic treatment tank 3 of plant according to the invention will be equipped with a device AL of conventional design and operation, by means of which to aerate the liquid.
EP19910830193 1990-05-18 1991-05-10 Procédé et installation pour l'épuration biologique d'eau usée Withdrawn EP0458760A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT4797690 1990-05-18
IT4797690A IT1240837B (it) 1990-05-18 1990-05-18 Procedimento ed impianto per la depurazione biologica delle acque reflue

Publications (1)

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EP0458760A1 true EP0458760A1 (fr) 1991-11-27

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IT (1) IT1240837B (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2042424A1 (es) * 1991-06-10 1993-12-01 Enea Ente Nuove Tec Procedimiento para la depuracion de liquidos en general, particularmente de las aguas residuales municipales, e instalacion que utiliza dicho procedimiento.
WO1995007861A1 (fr) * 1993-09-13 1995-03-23 Karsten Krogh Andersen Installation d'epuration permettant d'extraire des substances nutritives des eaux d'egout
FR2748742A1 (fr) * 1996-05-15 1997-11-21 Gtb Bouyer Duchemin Station d'epuration de liquides pollues et plus particulierement bassin d'aeration/anoxie d'une telle station
ES2128250A1 (es) * 1996-12-27 1999-05-01 Infilco Espanola S A Sistema de eliminacion biologica de nitrogeno y fosforo en un proceso que utiliza fangos activos.
NL1009590C2 (nl) * 1998-07-08 2000-01-11 Sirius B V Inrichting voor het zuiveren van afvalwater.
WO2000034188A1 (fr) * 1998-12-04 2000-06-15 Tox Olaopa Retrait biologique d'elements nutritifs selon la « methode olaopa »
ES2154174A1 (es) * 1998-09-08 2001-03-16 Rio Marrero Ignacio Del Sistema de paneles moviles para aislamiento de zonas con diferentes condiciones en procesos de fangos activados de depuracion de aguas residuales.
FR2837813A1 (fr) * 2002-03-29 2003-10-03 Omnium Traitement Valorisa Installation circulaire pour le traitement biologique des eaux usees
EP2154115A1 (fr) 2008-07-21 2010-02-17 Kelet-magyarországi Vállalkozási Épitöipari és Kereskedelmi Kft. Sous-éléments flexibles pour installation de traitement biologique d'eaux d'égout
CN101041509B (zh) * 2007-04-24 2010-05-19 上海亚同环保实业有限公司 循环流环型生物脱氮除磷工艺
CN102001799A (zh) * 2010-12-27 2011-04-06 江苏江大环境工程有限责任公司 一种高浓度有机废水的高效厌氧－耗氧组合处理装置
EP2274245A4 (fr) * 2008-04-17 2012-08-01 Alnarp Cleanwater Technology Ab Phytosystème destiné au traitement des eaux usées
CN104150720A (zh) * 2014-08-28 2014-11-19 深圳合续环境科技有限公司 气提式一体化污水处理装置
CN106186332A (zh) * 2016-09-06 2016-12-07 山东文远建材科技股份有限公司 户用污水处理设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109970193B (zh) * 2019-04-15 2024-04-09 浦华环保有限公司 强化型脱氮装置以及设备

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0100568A2 (fr) * 1982-08-04 1984-02-15 Metallgesellschaft Ag Procédé pour le traitement d'eau usée
USRE32429E (en) * 1976-04-12 1987-06-02 Air Products And Chemicals, Inc. Production of non-bulking activated sludge

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE32429E (en) * 1976-04-12 1987-06-02 Air Products And Chemicals, Inc. Production of non-bulking activated sludge
EP0100568A2 (fr) * 1982-08-04 1984-02-15 Metallgesellschaft Ag Procédé pour le traitement d'eau usée

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ENGINEERING. vol. 86, no. 28, December 1979, NEW YORK US pages 34 - 35; GALDIERI,J.V.: 'Biological phosphorus removal ' *
JOURNAL OF THE WATER POLLUTION CONTROL FEDERATION. vol. 60, no. 10, October 1988, WASHINGTON US pages 1833 - 1842; DAIGGER,G.T. ET AL.: 'Enhanced secondary treatment incorporating biological nutrient removal. ' *
KORRESPONDENZ ABWASSER. vol. 36, no. 3, March 1989, AUGUSTIN DE pages 337 - 348; ATV-ARBEITSBERICHTE: 'BIOLOGISCHE PHOSPHORENTFERNUNG ' *

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2042424A1 (es) * 1991-06-10 1993-12-01 Enea Ente Nuove Tec Procedimiento para la depuracion de liquidos en general, particularmente de las aguas residuales municipales, e instalacion que utiliza dicho procedimiento.
WO1995007861A1 (fr) * 1993-09-13 1995-03-23 Karsten Krogh Andersen Installation d'epuration permettant d'extraire des substances nutritives des eaux d'egout
FR2748742A1 (fr) * 1996-05-15 1997-11-21 Gtb Bouyer Duchemin Station d'epuration de liquides pollues et plus particulierement bassin d'aeration/anoxie d'une telle station
ES2128250A1 (es) * 1996-12-27 1999-05-01 Infilco Espanola S A Sistema de eliminacion biologica de nitrogeno y fosforo en un proceso que utiliza fangos activos.
NL1009590C2 (nl) * 1998-07-08 2000-01-11 Sirius B V Inrichting voor het zuiveren van afvalwater.
ES2154174A1 (es) * 1998-09-08 2001-03-16 Rio Marrero Ignacio Del Sistema de paneles moviles para aislamiento de zonas con diferentes condiciones en procesos de fangos activados de depuracion de aguas residuales.
WO2000034188A1 (fr) * 1998-12-04 2000-06-15 Tox Olaopa Retrait biologique d'elements nutritifs selon la « methode olaopa »
US6562237B1 (en) * 1998-12-04 2003-05-13 Tox Olaopa Biological nutrient removal using the olaopa process
CN1325401C (zh) * 2002-03-29 2007-07-11 Otv股份有限公司 用于废水的生物处理的圆形设备
WO2003082752A1 (fr) * 2002-03-29 2003-10-09 Otv S.A. Installation circulaire pour le traitement biologique des eaux usees.
FR2837813A1 (fr) * 2002-03-29 2003-10-03 Omnium Traitement Valorisa Installation circulaire pour le traitement biologique des eaux usees
CN101041509B (zh) * 2007-04-24 2010-05-19 上海亚同环保实业有限公司 循环流环型生物脱氮除磷工艺
EP2274245A4 (fr) * 2008-04-17 2012-08-01 Alnarp Cleanwater Technology Ab Phytosystème destiné au traitement des eaux usées
EP2274245B1 (fr) 2008-04-17 2015-03-25 Alnarp Cleanwater Technology AB Phytosystème, son utilisation et procédé destiné au traitement des eaux usées
EP2154115A1 (fr) 2008-07-21 2010-02-17 Kelet-magyarországi Vállalkozási Épitöipari és Kereskedelmi Kft. Sous-éléments flexibles pour installation de traitement biologique d'eaux d'égout
CN102001799A (zh) * 2010-12-27 2011-04-06 江苏江大环境工程有限责任公司 一种高浓度有机废水的高效厌氧－耗氧组合处理装置
CN102001799B (zh) * 2010-12-27 2013-04-24 江苏江大环境工程有限责任公司 一种高浓度有机废水的高效厌氧－耗氧组合处理装置
CN104150720A (zh) * 2014-08-28 2014-11-19 深圳合续环境科技有限公司 气提式一体化污水处理装置
CN104150720B (zh) * 2014-08-28 2016-08-24 深圳合续环境科技有限公司 气提式一体化污水处理装置
CN106186332A (zh) * 2016-09-06 2016-12-07 山东文远建材科技股份有限公司 户用污水处理设备

Also Published As

Publication number Publication date
IT9047976A1 (it) 1991-11-18
IT1240837B (it) 1993-12-17
IT9047976A0 (it) 1990-05-18

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